Secret Wars #4 looks like it will reveal quite a bit of blanks. Why does Doctor Strange follow Doctor Doom. How did Battleworld become constructed. This will be an interesting meeting between a group of the survivors of the 616 universe and their old friend.

Another interesting thing will be when Reed realizes that Sue and his children in a way are alive.

Variant Covers:
The main cover is awesome. Its a Ross cover with Doom sitting on a throne made of the world tree Yggidrasil with his special family sitting around him. While I really like it, there are some variants that stand out. My personal favorite of these is a stained glass Carol Danvers cover. Something about the art work on that cover I find very striking. Its like a religious iconography intermixed with comic super hero work. The Captain America action figure variant is also pretty cool.

Now for the interior preview:
I really like the white and grey intros. They add a degree of simplicity and also add a kind of subliminal weight that creates an aura of importance as the reader enters the story.

Another Carol Danvers mention here. She looks bad ass in the picture below.